1. Field of the Invention
This invention relates to a data communication system and method through which a controller and a controlled device controlled by the controller perform data communication via a communication channel, and to the controller and controlled device that construct this data communication system. The invention relates further to a digital video camera and printer. The invention relates further to a method of controlling the storage of driver software and a method of reading out the driver software.
This invention relates further to a battery charging apparatus capable of being connected to a communication apparatus, which is capable of performing data communication via a communication channel, using this communication channel to make the connection. The invention relates further to a method of charging a battery.
2. Description of the Related Art
In a data communication system through which a controller (a personal computer) and a controlled device (a printer or digital video camera, etc.) perform data communication via a communication channel, it is necessary to install driver software in the controller in order to control the controlled device using the controller. In the prior art, the user loads a floppy disk or CD-ROM, on which driver software suited to the controlled device has been stored, into a floppy disk drive or CD-ROM drive of the controller. The driver software is then installed in the controller by being read out of the floppy disk or CD-ROM. However, performing installation by loading the floppy disk or CD-ROM into the floppy disk drive or CD-ROM drive is a troublesome operation for the user. In addition, there are occasions where the user accidentally installs driver software not suited to the controlled device.
On the other hand, in order to send and receive image data, use is made of parallel communication by relying upon a Centronics interface or SCSI (Small Computer System Interface), etc., and serial communication using an RS232C, RS422 or USB (Universal Serial Bus). With serial communication, only the sending and receiving of image data is performed and consideration has never been given to charging a battery by utilizing an image-data communication channel. If a battery is to be charged, a charging device must be connected via a separate power supply cable.